The present invention is direct to structures for supporting a patient in a desired position during examination and treatment, including medical procedures such as imaging and surgery and in particular to such a structure that allows a surgeon to selectively position the patient for convenient access to the surgery site for manipulation of the patient during surgery including the tilting, pivoting, angulating or bending of a trunk and additionally or alternatively joint of a patient in a supine, prone or lateral-decubitus position, while simultaneously maintaining the patient's head in a convenient location for anesthesia and substantially preventing undesired stretching or compression of the patient's spine and the patient's skin.
Current surgical procedures and approaches incorporate imaging techniques and technologies that facilitate the surgical plan and improve outcomes and that provide for more rapid patient recovery. For example, minimally invasive surgical techniques, such as percutaneous insertion of spinal implants, involve small incisions that are guided by continuous or repeated intra-operative imaging and that are frequently associated with navigation technologies. These imaging and navigation techniques can be processed using computer software programs that produce two or three dimensional images for reference by the surgeon during the course of the procedure. If the patient support structure, apparatus, system or device is not radiolucent or configured to be compatible with the imaging technologies, it may be necessary to interrupt the surgery periodically in order to remove the patient to a separate structure for imaging followed by transfer back to the operating support structure for resumption of the surgical procedure. Such patient transfers for imaging purposes may be avoided by employing radiolucent and other imaging and navigation compatible systems. The patient support system should also be constructed to permit unobstructed movement of the imaging equipment and other surgical equipment around, over and under the patient throughout the course of the surgical procedure without contamination of the sterile field.
It is also necessary that the patient support structure be constructed to provide optimum access to the surgical field by the surgery team. Some procedures require positioning of portions of the patient's body in different ways at different times during the procedure. Some procedures, for example, spinal surgery, involve access through more than one surgical site or field. Since all of these fields may not be in the same plane or anatomical location, the patient support surfaces should be adjustable and capable of providing support in different planes for different parts of the patient's body as well as different positions or alignments for a given part of the body. Preferably, the patient support should be adjustable to provide support in separate planes and in different alignments for the head and upper trunk portion of the patient's body, the lower trunk and pelvic portion of the body as well as each of the limbs independently.
Certain types of surgery, such as orthopedic surgery, may require that the patient or a part of the patient be repositioned during the procedure while in some cases maintaining the sterile field. Where surgery is directed toward motion preservation procedures, such as by installation of artificial joints, soft or dynamic stabilization implants, spinal ligaments and total disc prostheses, for example, the surgeon must be able to manipulate certain joints while supporting selected portions of the patient's body during surgery in order to facilitate the procedure. It is also desirable to be able to test the range of motion of the surgically repaired or stabilized joint and to observe the gliding movement of the reconstructed articulating prosthetic surfaces or the tension and flexibility of artificial ligaments, cords, spacers and other types of dynamic stabilizers before the wound is closed. Such manipulation can be used, for example, to verify the correct positioning and function of an implanted prosthetic disc, spinal dynamic longitudinal connecting member, interspinous spacer or joint replacement during a surgical procedure. Where manipulation discloses binding, sub-optimal position or even crushing of the adjacent vertebrae, for example, as may occur with osteoporosis, the prosthesis can be removed and the adjacent vertebrae fused or otherwise treated while the patient remains anesthetized. Injury which might otherwise have resulted from a “trial” use of the implant post-operatively will be avoided, along with the need for a second round of anesthesia and surgery to remove the implant or prosthesis and perform the revision, fusion or corrective surgery.
There is also a need for a patient support structure that can be rotated, articulated and angulated so that the patient can be moved or rolled from a supine position to a prone position, or from a lateral-decubitus to a supine position, or from a prone position to a position with the hips and knees flexed or extended, and whereby intra-operative extension and flexion of at least a portion of the spinal column can be achieved to change lumbar lordosis. The patient support structure must also be capable of cooperating with the biomechanics of the patient for easy, selective adjustment without necessitating removal of the patient or causing substantial interruption of the procedure.
For certain types of surgical procedures, for example spinal surgeries, it may be desirable to position the patient for sequential anterior, posterior and additionally or alternatively lateral procedures. The patient support structure should also be capable of rotation about an axis in order to provide correct positioning of the patient and optimum accessibility for the surgeon as well as imaging equipment during such sequential procedures, and also without translating the patient's head, which could disrupt connection of the patient with anesthesia equipment, and also without undesirably distracting or compressing the patient's spine during angulation or rotation of the patient's pelvis around the hips.
Orthopedic procedures involving fractures and other trauma may require the use of traction equipment such as cables, tongs, pulleys and weights. The patient support system must include structure and accessories for anchoring such equipment and it must provide adequate support to withstand unequal forces generated by traction against such equipment.
Orthopedic procedures, especially spine surgery, may also require the use of an open frame, instead of a closed table top, that allows a prone patient's belly to hang downwardly therebetween so as to prevent compression of internal organs against the anterior side of the patient's spine and prevent compression of the patient's vessels to decrease blood loss.
Articulated robotic arms are increasingly employed to perform surgical techniques. These units are generally designed to move short distances and to perform very precise work. Reliance on the patient support structure to perform any necessary gross movement of the patient can be beneficial, especially if the movements are synchronized or coordinated. Such units require a surgical support surface capable of smoothly performing the multi-directional movements which would otherwise be performed by trained medical personnel. There is thus a need in this application as well for integration between the robotics technology and the patient positioning technology.
While conventional operating tables generally include structure that permits tilting or rotation of a patient support surface about a longitudinal axis, previous surgical support devices have attempted to address the need for access by providing a cantilevered patient support surface on one end. Such designs typically employ either a massive base to counterbalance the extended support member or a large overhead frame structure to provide support from above. The enlarged base members associated with such cantilever designs are problematic in that they can and do obstruct the movement of C-arm and O-arm mobile fluoroscopic imaging devices and other equipment. Surgical tables with overhead frame structures are bulky and may require the use of dedicated operating rooms, since in some cases they cannot be moved easily out of the way. Neither of these designs is easily portable or storable. More recent orthopedic surgical tables require complicated mechanisms to provide translation of the patient's trunk while manipulating the patient's lower body during surgery.
More recent and advanced articulating surgical tables are available, and include an open frame patient support for positioning with upper and lower body support portions joined by centrally located and spaced apart hinges. However, while these surgical tables enable bending the patient at the waist or hips, maintaining the vertical height of the surgical site can be difficult. These tables can also cause significant translation of the patient's trunk toward and away from anesthesia, which is undesirable. These tables also require complex translation compensation structural mechanisms to prevent potential patient injury.
Thus, there remains a need for a patient support structure that provides easy access for personnel and equipment, that can be easily and quickly positioned and repositioned in multiple planes without the use of massive counterbalancing support structure, that can maintain the patient's head at a convenient location for anesthesia during positioning of the patient, that does not cause undesired stretching or compression of the patient's spine and skin and that does not require use of a dedicated operating room.